Regarding Educational Institutions

what is the context for your query?

are services provided by Icai to its students exempt under entry 66?

educational institution means an institute which provides services by way of
a. preschool education and education upto higher secondary or equivalent
b. education as a part of curriculum for obtaining qualifications recognised by law.
c education as a part of approved vocational course.

ICAI is covered under (b) category hence services provided by icai to its student is exempt

Yes it is excempted